Switch module

Abstract

A switch module includes a switch circuit, a chip device which is a coupler, a chip device that defines together with the coupler a common-terminal-side circuit, chip devices defining switching-terminal-side circuits, and a multilayer substrate. The multilayer substrate includes inner-layer ground electrodes. A first inner-layer ground electrode is closer to the chip device than a second inner-layer ground electrode and includes an opening arranged so as not to be superposed with the chip device when viewed in plan in the stacking direction of the multilayer substrate.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to a switch module configured to receive and transmit a plurality of communication signals using a common antenna.[0003]2. Description of the Related Art[0004]In recent years, a communication apparatus has come to transmit and receive a plurality of communication signals in different frequency bands using a common antenna, as cellular phones and the like have come to use multiple bands (refer to, for example, Japanese Unexamined Patent Application Publication No. 2008-10995). As a result, a communication apparatus has increasingly utilized a switch module that connects a plurality of communication circuits to a common antenna through switching.[0005]FIG. 6A is a block diagram illustrating a general circuit configuration of a switch module.[0006]A front-end circuit FEC illustrated in FIG. 6A includes a switch circuit SW, a common-terminal-side circuit 104, and switching-terminal-side circuit...

AI Technical Summary

Benefits of technology

[0014]Hence, preferred embodiments of the present invention provide a switch module that significantly reduces or prevents generation of coupling through an inner-layer ground electrode and achieves favorable characteristics.

[0018]With these configurations, the occurrence of the first circuit device being coupled to other common devices through the inner-layer ground electrode closest to the first circuit device is significantly reduced or prevented. As a result, generation of undesired coupling within the common-terminal-side circuit and generation of undesired coupling between the common-terminal-side circuit and the switching-terminal-side circuits are significantly reduced or prevented. Hence, degradation in the characteristics of the switch module is prevented.

[0021]With these configurations, coupling between the main line and sub line of the coupler through the inner-layer ground electrode that is closest to the coupler, which is the first circuit device, is significantly reduced or prevented, such that degradation in the characteristics of the switch module is prevented.

[0024]According to various preferred embodiments of the present invention, the inner-layer ground electrode closest to the first circuit device is not superposed with the first circuit device when viewed in plan in the stacking direction of the multilayer substrate. Hence, the occurrence of the common-terminal-side circuit being coupled to the switching-terminal-side circuit through the inner-layer ground electrode is significantly reduced or prevented. Further, generation of undesired coupling within the common-terminal-side circuit is significantly reduced or prevented. As a result, degradation in the characteristics of the switch module is prevented.

Problems solved by technology

These couplings, which degrade isolation characteristics among the chip devices, cause degradation in the characteristics of the front-end circuit FEC.

Images